Update Plugin.php

Author: creecros

Plugin.php

@@ -3,6 +3,7 @@
 namespace Kanboard\Plugin\Group_assign;
 
 use Kanboard\Core\Plugin\Base;
+use Kanboard\Core\Translator;
 use Kanboard\Model\TaskModel;
 use Kanboard\Model\ProjectGroupRoleModel;
 use Kanboard\Plugin\Group_assign\Model\NewTaskFinderModel;